Process of producing paper



July 14, 1925 1,545,634 C. S.- BIRD PROCESS OF PRODUCING PAPER Filed Feb. 9, 1925 Patented-July l4, 1925.

"erran TATE-s CHARLES s. BIRD, or WALIOLE, ASSACHU ETTS.

I rnoonss or rn'onuomo PAPER.

Application filed February 9, 1925. Serial No. 8,062.

To all whom it may concern:

Be it knownthat I, CHAnIiEs S. BIRD, a citizen of the United States, residin at Walpole, in the county of Norfolk and tate of Massachusetts, have invented certain new and useful. Processes of Producing Paper, of which the following is aspecification.

This invention pertains to an improved process of producing paper and more particularly to an improved process of subdividing a web of paper into a plurality of strips. The invention is especially applicable to the slitting of that class of paper ordinarily manufactured in webs 'havin certain zones or areas extending longitud nally of the web of a thickness lessthau the] remainder of the body, the slitting being etl'ected through or immediately adjacent to the thin portions thereby producing strips or sheets having one or bothedges thin.

- The main object of'the invention is'to provide an improved process for slittingthe paper so that the strips produced will be free from wrinkles and ragged or cut edges.

I-Ieretofore paper'oi the kind above mentioned has been slit either p1 ior to the'jdrying operations as described in the patent to l-lanscom, No. 702,205, dated June. 10th, 1902. or in the, usual manner, on most all paper machines, after the calendering operation and prior to cutting the strips into sheets or to winding the same into rolls, For certain classes of uses of paper it has been found undesirable to utilizethe process of slitting prior to the dnving'operation. In such cases it has beencustomary to slit the web according to the usual paper makers practice; that is, after the paper has passed through the calender rolls, with the result of causing unequal strains and stresses upon the thin portions of the web thereby causing wrinkles 0r Calender cuts and consequently rendering a large portion of the paper unfit for commercial use. The present invention affords a method whereby such wrinkles and calender cuts in the edges of the sheet are practically not wholly eliminated. What is more, the sheets produced by the present method will expand but little when subjected to moisture,

With a view of more clearly outlining the process and illustrating means whereby the process may be carried out, reference will be had to the annexed drawings, wherein Fig. 1 1s a sectional elevation of a drier, a

calender stand, an interposed web slitting means and a spreader for the web after it has been slit;

Fig. 2 a plan view thereof with parts broken away;

Fig. 3 a transverse sectional view on an enlarged scale on the line II'I-III of Fig. 2, illustrating the spreader; and

Fig. 4 a detail view showing a slightly modified arrangement of the driers and slitters.

In so far as the process is concerned, the drawings are to be considered as merely illustrative.

Referring to Figs. 1 to nated by l emanating from the wet end of the machine (not shown) passes over and about the drier drums Q, 3 and 4,'as is usual. Located ad acent drum -lin suitable fixed bearings is a roller 5 over which the web passes unmediately it leaves said drum. Lo-

rated to the rear of the roller is a fixed rail or bar (3 which forms the support tor ,a series of bracket-s '7 adjustable longitudinally thereof with a-view of securing the spacing desired betweenthe brackets. To each bracket there is pivotally secured a weighted lever 8, each lever in turn carrying a slitting roll or diskl); The slitting disks bear upon the. roller 5 and-as a consequence slit the web 1 into a series of strips as the same is drawn beneath the disks.

The lines of severance may be centrally of results? may be effected by the. proper'adjustment and spacing of the brackets along the bar (3. i The web after having been cut 3, the web desiginto strips, or more properly speaking, the

strips, passes over a spreader illustrated as a flexible bar 10 secured to the upper ends of a series of brackets 11, which latter in turn are secured for vertical adjustment to r a fixed bar 12.

The spreader bar 10 will be given such upward curvature as wlll produce the desired spread or spacing between the various web strips asthey pass to the upper portion of the stand of calendering rolls designated generally by 13.

In Fig. 4 a slight variation of the drying drums and slitters is shown. In this instance the shtters act upon the web at a .point between the last two drums 3 and 1% the web at such time having been sutliciently dried by the drums 2% and 3 to allow the. slitters to act upon the thin portions of extent than after drying,

ter suited for some purposes than that which.

results from the old method of cutting,

namely, slitting before drying the web. The

paper is smoother and does not expand as readily in the presence of moisture. This latter qualityis due to the fact that the web is held finder lateral tension by the drying drums (or some of them atvleast) prior to its being cut into strips. When cut before being dried, thefibers contract to a greater and consequently ,will expand to a greater xtent in the presence fmoisture.

"-' Where sheets having a thinned edge ortwo thinned edgesare employed in the man-.

; ufacture of articles Which require accuracy of size, such, forinstance, ashigh gradeshot shells, the presence of cuts or Wrinkles along such thinned edges is fatal to a sube cut, n0 difficult arises as the edges are smooth and even, eing free from wrinkles and calender cuts.

.What is claimed is:

paper having thin edges from a Web having thin zones extending longitudinally thereof, which consists in drying the Web; slitting the same along the thin zones; and thereafter calendering the strips.

2. That process of producing strips of paper having thin edges from a web having thin zones extending longitudinally thereof which consists in passing the web through a drier; slitting the web along such zones as it leaves the drier; spreading the strips; and finally calendering the separated strips.

3..In a machine for producing strips of paper having at least one thin edge comprising in combination means foradrying a web having at least one thin section; means for slitting the web at said drying means; means for spreading the strips thus produced; and means for calendering the strips.

In testimony whereof I have signed my name to this specification.

CHARLES S. BIRD.

. 1. That process of producing strips of a 

